Improvement in hinges



C. B. CLARK.

. HINGES. No.18Z,89-3. Patented 001:.3, 187e.

NITED STATES PATENT OFFICE.

CHARLES B. CLARK, OF BUFFALO, NEW YORK.

IMPROVEMENT iN HlNeEs.

Specification forming part of Letters Patent No. 182,893, dated October3, 1876; application filed July 22, 1876.

To all whom it may concern:

Be it known that I, CEAnLEs B. CLARK, of Bualo, in the county of Erieand State of New York, have invented certain new and useful Improvementsin Butt-Hin ges, of which the following is a specification:

This invention vrelates to certain improvements in hinges; and consistsin providing a removable pintle with a knob having a iiatbearing-surface at its inner end of a diameter less than the body of theknob, while the knuckle-joint of the hinge is formed with abearing-surt'ace'at its upper end of a-diameter less than the diameterof the main body of the knuckle, in such a manner that a contracted-neckbearin g-surface is obtained, making a neat close-fitting joint betweenthe parts, as well as cheapenin g the cost of manufacture and addinggreatly to the beauty and ornamental appearance of the article.

Hitherto the general method has been to cast the knob on the pintle-Wireagainst an iron chill, forming a concave shoulder or bearing ofsufficient size to meet the diameter of the knuckle of the hinge, theobject of the chill being to cast a smooth surface at the joint, andsufficiently concave to cover any irregularities atthe end of theknuckle-joint. This method must be adopted, or else the end of theknuckle-joint countersunk so as to meet the convex shoulder-joint of theknob, for it is impossible to cast a deep shoulder Without having somedraft, in order to have it mold well, and even then it is always liableto be rough at the division of the molds.

Either method mentioned adds to the cost of production, and from theextent and usual roughness of the joint is objectionable to theappearance of the hinge.

I avoid these objections and lessen the cost by making the division orseat at the neck or smallest part of the knob, thereby requiringscarcely any draft for the slight shoulder around the pintle-wire of theneck portion of the knob.

I am thus enabled to make, at no additional expense beyond the ordinarysimple process of molding, a closely-fitting joint, and the pintle-Wireis also more securely held within the knob, extending, as it does, intothe larger diameter of the saine, whereas in the other methods shown theknobs are liable to break off at the necks in withdrawing them from thehinge when the door is hung, for itis quite impossible to cast thepintle through the undivided neck without making blow-holes in thecasting; and for the above reasons I am also enabled to make a smallerand more symmetrical neck, which the more eiectually conceals thedividingjoint and preserves the knuckle-joint line unbroken. These areimportant considerations iii the manufacture of this class of hinges, asthey facilitate the production and cheapen the article to the trade.

Figure 1 represents a sectional view of a hinge in which the base orbearing-surface of the knob is cast concave by means of the iron chill,for the purpose before mentioned. Fig. 2 is a similar view, showing thebase of the knob convex at its bearing, with a corresponding countersinkin the end of the hingeknuckle. Fig. 3 is a like view of a hinge showinginy improved division of the pintleknob, and Fig. 4 the pintle and itsknob detached.

The hinge is reversible for right and left hand doors, and isconstructed in the usual manner, except in the particulars of myiinprovement, which consists in making the bearing or seat a of the knobat the neck or least diameter thereof-that is to say, the neck isdivided at a point to leave the larger or base portion c upon the end ofthe knuckle d, and obtain thereby the smallest bearing-surface, andwhich avoids the expensive employment of iron chills and insures a closefit of the pintie-knob with the hinge-knuckle d. In Figs. 1 and 2 thebearing or seat is the full diameter of the knuckle, as at e, while inFig. 3 a portion of the knob-neck is formed upon the knuckle, and of ashape and diameter symmetrical with the neck, so that the seat is at theneck and not at the base of the knob, as in Figs. 1 and 2. Thecorresponding knob at the other end of the knuckle is cast solidly Withthe hinge.

I do not confine my improvements to the ordinary acorn or to anyspecific shape of the knob, as my object is to divide the knob at itssmallest diameter, irrespective of' its pecu liar shape, and for thepurpose hereinbefore mentioned.

I do not herein claim any part of the design or ornamentation, the samehaving been allowed me in another application for the de sign only,filed under date of September 11, 1876, and intended to be taken out asof even date herewith; but

What I claim, and desire to secure by Letters Patent, is

The removable pintle of a hinge, provided with a knob, having a datbearing-surface at its inner end of a diameter less than the diameter ofthe knob, in combination with the CHARLES B. CLARK.

Witnesses: J oHN HoLEHoUsE, CHAs. J. CHRETIEN.

